I have special planars for sale - praised in various reviews:
headphonecheck.com/test/avantone-pro-planar/
majorhifi.com/avantone-pro-planar-headphone-review/

I bought the headphones here on Head-Fi from @smorgar - he bought them on Thomann on 11/11/2020 and I have an e-receipt for it, so they are still under warranty in Thomann and Avantone.
The previous owner made some improvements - he applied additional padding to the headband from Sennheiser HD555 / 595 to increase comfort and replaced rubber between yokes with a 3-D printed one. Besides, they are exactly like from the factory.
The set includes everything that manufacter has given.
Sound-wse, they are one of the most neutral headphones I know.
Price 320 + shipping